Crohn's Disease Presenting With Secondary Immunoglobulin A Nephropathy and Cutaneous Vasculitis: Unusual Extraintestinal Manifestations

Crohn's disease (CD) can rarely present with extraintestinal complications involving the renal and cutaneous systems. We describe a 19-year-old man who initially presented with palpable purpura and proteinuria and was diagnosed with leukocytoclastic vasculitis and Immunoglobulin A nephropathy. He subsequently developed fecaluria and abdominal pain, and further evaluation confirmed fistulizing CD with enterovesical fistulae. Initiation of infliximab and azathioprine resulted in clinical improvement and weight gain. This case highlights that CD may exhibit atypical extraintestinal manifestations, such as cutaneous and renal manifestations, which may precede the development of full-blown fistulizing CD. Early recognition and multidisciplinary management are key to prevent complications.